The present invention relates to a dispenser for dispensing liquid from a receptacle, and more particularly it relates to a miniature pump for delivering samples of perfumes or cosmetics or very small doses of pharmaceuticals, for example.
Miniature dispensers as described and shown in EP-A-0 453 357 comprise in particular a cylindrical and conical body enclosing a metering chamber closed at its bottom end by an admission valve and in its top portion by a piston provided with a delivery valve, and a delivery tube capped by a pushbutton.
Nevertheless, in conventional bodies that are made as a single piece, the piston is generally inserted into the chamber through the top opening and is then pushed downwards into the chamber, thereby giving rise to upward remanent deformation of the peripheral edge of the piston.
Unfortunately, this poor disposition of the edge of the piston is very difficult to correct after assembly, and if it is not corrected it runs the risk of causing the piston to jam and also of allowing liquid to leak out.
Furthermore, the pushbutton is held on the dispenser merely by being engaged on the delivery tube, which does not give it very great stability and which does not suffice to keep it in place when subjected to accidental stresses.
In addition, in traditional dispensers, the body must be sufficiently flexible to guarantee good sealing and proper operation of the valves, but it must also be sufficiently rigid to enable it to withstand temperature and aging well, particularly in the contact zone between the piston and the wall of the chamber. These constraints imposed on the material constituting the body determine the regularity and the constancy of the successive quantities of liquid that are dispensed.
Furthermore, it may be necessary to raise the body relative to the neck, which is either not possible with dispensers of the above type, or else leads to discontinuities in appearance.
An object of the invention is to resolve these technical problems in satisfactory manner.
According to the invention, this object is achieved by means of a dispenser of the above type in which said bottom element provided with a sleeve for co-operating with said skirt by leaktight radial clamping to define the wall of said measuring chamber, the dispenser being characterized in that said bottom element is provided with a bushing extending said sleeve coaxially downwards for engaging with leaktight radial clamping inside the neck of the receptacle.
In a particular embodiment, said skirt is engaged inside said sleeve.
Preferably, the bottom edge of said skirt comes into contact with the inside wall of said sleeve.
According to an advantageous characteristic, said skirt carries a shoulder forming an abutment for the top edge of said sleeve.
According to another characteristic, the inside wall of said skirt carries a radial projection for retaining the piston and/or the pushbutton.
In a particular embodiment, the admission valve is carried by the bottom element being provided at the bottom portion of said sleeve.
In a variant, said sleeve or said skirt carries a support and fixing collar on the neck of the receptacle.
In another variant, said collar is provided with screw-fastening or snap-fastening members for cooperating with complementary members of the receptacle.
The dispenser of the invention possesses a body made up of two elements that are made separately in independent form and that are designed to be assembled together either directly on the manufacturing site or else subsequently on the site where a product is packaged.
This concept makes a wide range of different functions, materials, and/or hardnesses available respectively for the top element and for the bottom element which can now be associated in a single dispenser, thus making it possible to optimize performance and in particular to optimize the quality and the reliability of dispensing.
In addition, the dispenser can be mounted on a receptacle move easily and in more diverse manners, thus enabling appearance to be improved without compromising leaktightness.
Finally, this disposition makes it possible firstly to introduce the piston from below into the top element, i.e. in compliance with its functional orientation, and secondly to retain both said piston and the pushbutton in an upward direction by using means that are simple and compatible with the return forces produced by a spring if any.